Easter egg: This in the normal DVD version of Zoolander. Go to the second page of the special features menu. Then highlight the feature that is right above the Mugatu symbol. Hit right. It will take you to the walk off rehearsals.

When Zoolander, Hansel and Matilda are drinking the tea near the end of the movie, the "steam" in Zoolander's cup keeps on changing to from overflowing the cup, to half way down and none. This is without ever refilling his cup. He can even be seen blowing some of the steam out and next thing it's full again.